package yunjiao.javatutorials.guava.concurrent.timed;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 连接池监控
 *
 * @author yangyunjiao
 */
public class ConnectionPool {
    private final Lock lock = new ReentrantLock();
    private final TimedCondition connectionAvailable;
    private final int maxConnections;
    private int activeConnections = 0;

    public ConnectionPool(int maxConnections) {
        this.maxConnections = maxConnections;
        this.connectionAvailable = new TimedCondition(lock.newCondition());
    }

    public Connection getConnection(long timeout, TimeUnit unit)
            throws InterruptedException, TimeoutException {
        lock.lock();
        try {
            long startTime = System.currentTimeMillis();
            long timeoutMs = unit.toMillis(timeout);

            while (activeConnections >= maxConnections) {
                boolean gotConnection = connectionAvailable.await(
                        timeoutMs, TimeUnit.MILLISECONDS);

                if (!gotConnection) {
                    throw new TimeoutException("获取连接超时");
                }
            }

            activeConnections++;
            System.out.println("获取连接成功，当前活跃连接: " + activeConnections);
            return new MockConnection();

        } finally {
            lock.unlock();
        }
    }

    public void releaseConnection(Connection connection) {
        lock.lock();
        try {
            activeConnections--;
            connectionAvailable.signal();
            System.out.println("释放连接，当前活跃连接: " + activeConnections);
        } finally {
            lock.unlock();
        }
    }

    public void printPoolStatistics() {
        connectionAvailable.printStatistics();
    }

    // 模拟连接类
    private static class MockConnection implements Connection {
        @Override
        public Statement createStatement() throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql) throws SQLException {
            return null;
        }

        @Override
        public CallableStatement prepareCall(String sql) throws SQLException {
            return null;
        }

        @Override
        public String nativeSQL(String sql) throws SQLException {
            return null;
        }

        @Override
        public void setAutoCommit(boolean autoCommit) throws SQLException {

        }

        @Override
        public boolean getAutoCommit() throws SQLException {
            return false;
        }

        @Override
        public void commit() throws SQLException {

        }

        @Override
        public void rollback() throws SQLException {

        }

        public void close() {
            // 连接关闭逻辑
        }

        @Override
        public boolean isClosed() throws SQLException {
            return false;
        }

        @Override
        public DatabaseMetaData getMetaData() throws SQLException {
            return null;
        }

        @Override
        public void setReadOnly(boolean readOnly) throws SQLException {

        }

        @Override
        public boolean isReadOnly() throws SQLException {
            return false;
        }

        @Override
        public void setCatalog(String catalog) throws SQLException {

        }

        @Override
        public String getCatalog() throws SQLException {
            return null;
        }

        @Override
        public void setTransactionIsolation(int level) throws SQLException {

        }

        @Override
        public int getTransactionIsolation() throws SQLException {
            return 0;
        }

        @Override
        public SQLWarning getWarnings() throws SQLException {
            return null;
        }

        @Override
        public void clearWarnings() throws SQLException {

        }

        @Override
        public Statement createStatement(int resultSetType, int resultSetconcurrent) throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetconcurrent) throws SQLException {
            return null;
        }

        @Override
        public CallableStatement prepareCall(String sql, int resultSetType, int resultSetconcurrent) throws SQLException {
            return null;
        }

        @Override
        public Map<String, Class<?>> getTypeMap() throws SQLException {
            return null;
        }

        @Override
        public void setTypeMap(Map<String, Class<?>> map) throws SQLException {

        }

        @Override
        public void setHoldability(int holdability) throws SQLException {

        }

        @Override
        public int getHoldability() throws SQLException {
            return 0;
        }

        @Override
        public Savepoint setSavepoint() throws SQLException {
            return null;
        }

        @Override
        public Savepoint setSavepoint(String name) throws SQLException {
            return null;
        }

        @Override
        public void rollback(Savepoint savepoint) throws SQLException {

        }

        @Override
        public void releaseSavepoint(Savepoint savepoint) throws SQLException {

        }

        @Override
        public Statement createStatement(int resultSetType, int resultSetconcurrent, int resultSetHoldability) throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetconcurrent, int resultSetHoldability) throws SQLException {
            return null;
        }

        @Override
        public CallableStatement prepareCall(String sql, int resultSetType, int resultSetconcurrent, int resultSetHoldability) throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql, int autoGeneratedKeys) throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql, int[] columnIndexes) throws SQLException {
            return null;
        }

        @Override
        public PreparedStatement prepareStatement(String sql, String[] columnNames) throws SQLException {
            return null;
        }

        @Override
        public Clob createClob() throws SQLException {
            return null;
        }

        @Override
        public Blob createBlob() throws SQLException {
            return null;
        }

        @Override
        public NClob createNClob() throws SQLException {
            return null;
        }

        @Override
        public SQLXML createSQLXML() throws SQLException {
            return null;
        }

        @Override
        public boolean isValid(int timeout) throws SQLException {
            return false;
        }

        @Override
        public void setClientInfo(String name, String value) throws SQLClientInfoException {

        }

        @Override
        public void setClientInfo(Properties properties) throws SQLClientInfoException {

        }

        @Override
        public String getClientInfo(String name) throws SQLException {
            return null;
        }

        @Override
        public Properties getClientInfo() throws SQLException {
            return null;
        }

        @Override
        public Array createArrayOf(String typeName, Object[] elements) throws SQLException {
            return null;
        }

        @Override
        public Struct createStruct(String typeName, Object[] attributes) throws SQLException {
            return null;
        }

        @Override
        public void setSchema(String schema) throws SQLException {

        }

        @Override
        public String getSchema() throws SQLException {
            return null;
        }

        @Override
        public void abort(Executor executor) throws SQLException {

        }

        @Override
        public void setNetworkTimeout(Executor executor, int milliseconds) throws SQLException {

        }

        @Override
        public int getNetworkTimeout() throws SQLException {
            return 0;
        }

        @Override
        public <T> T unwrap(Class<T> iface) throws SQLException {
            return null;
        }

        @Override
        public boolean isWrapperFor(Class<?> iface) throws SQLException {
            return false;
        }
    }

    public static void main(String[] args) throws Exception {
        ConnectionPool pool = new ConnectionPool(2);

        // 模拟多个线程获取连接
        List<Thread> threads = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            Thread thread = new Thread(() -> {
                try {
                    Connection conn = pool.getConnection(3, TimeUnit.SECONDS);
                    Thread.sleep(1500); // 模拟使用连接
                    pool.releaseConnection(conn);
                } catch (Exception e) {
                    System.out.println("线程 " + Thread.currentThread().getName()
                            + " 错误: " + e.getMessage());
                }
            });
            threads.add(thread);
            thread.start();
        }

        for (Thread thread : threads) {
            thread.join();
        }

        pool.printPoolStatistics();
    }
}
